It does and if not then Audition certainly does. but then again I wouldn't know what a dehummer filter does so wouldn't know to try it. I just don't have the 'sound edting' vocabulary yet :(

Audition has an excellent noide reduction facility. You can select a piece of sound just containing the noise to remove then apply that as a noise filter across everything else. Works a treat generally, but in this case it leaves my voice sounding a little 'tinny'. takes about of the low frequencies away i guess.

But having said all this, I'll try a reshoot anyway. I want a single shot and there's way too much dialogue anyway. I'm at my PC now to re-script it. Take the 5 minute phone coversation down to about 2

This is the first time I've ever shot a scripted story and I'm learning loads - mostly by trial and error. All my work till now has been editing family occasions and holidays and stuff like that. This is more fun though.